fix: config hostname as string type in kubeadmConfig rendering

[ErikJiang]

What type of PR is this?
/kind bug

What this PR does / why we need it:
When rendering the kubeadm configuration file, the hostname may sometimes be a numeric name.
If double quotes are not added, kubeadm init may detect it as a numeric type and throw an error.

Examples of such error messages are as follows:

{
   "attempts":3,
   "changed":true,
   "cmd":[
      "timeout",
      "-k",
      "300s",
      "300s",
      "/usr/local/bin/kubeadm",
      "init",
      "--config=/etc/kubernetes/kubeadm-config.yaml",
      "--ignore-preflight-errors=all",
      "--v=8",
      "--skip-phases=addon/coredns",
      "--upload-certs"
   ],
   "delta":"0:00:01.092516",
   "end":"2024-01-30 21:48:15.252523",
   "failed_when_result":true,
   "msg":"non-zero return code",
   "rc":1,
   "start":"2024-01-30 21:48:14.160007",
   "stderr":"I0130 21:48:14.241241   25813 initconfiguration.go:255] loading configuration from \"/etc/kubernetes/kubeadm-config.yaml\"\nW0130 21:48:14.247196   25813 initconfiguration.go:307] error unmarshaling configuration schema.GroupVersionKind{Group:\"kubeadm.k8s.io\", Version:\"v1beta3\", Kind:\"ClusterConfiguration\"}: json: cannot unmarshal number into Go struct field APIServer.apiServer.certSANs of type string\njson: cannot unmarshal number into Go struct field APIServer.apiServer.certSANs of type string",
   "stderr_lines":[
      "I0130 21:48:14.241241   25813 initconfiguration.go:255] loading configuration from \"/etc/kubernetes/kubeadm-config.yaml\"",
      "W0130 21:48:14.247196   25813 initconfiguration.go:307] error unmarshaling configuration schema.GroupVersionKind{Group:\"kubeadm.k8s.io\", Version:\"v1beta3\", Kind:\"ClusterConfiguration\"}: json: cannot unmarshal number into Go struct field APIServer.apiServer.certSANs of type string",
      "json: cannot unmarshal number into Go struct field APIServer.apiServer.certSANs of type string"
   ],
   "stdout":"",
   "stdout_lines":[
      
   ]
}

{
   "attempts":3,
   "changed":true,
   "cmd":[
      "timeout",
      "-k",
      "300s",
      "300s",
      "/usr/local/bin/kubeadm",
      "init",
      "--config=/etc/kubernetes/kubeadm-config.yaml",
      "--ignore-preflight-errors=all",
      "--skip-phases=addon/coredns",
      "--upload-certs"
   ],
   "delta":"0:00:00.043053",
   "end":"2024-03-06 04:53:59.038113",
   "failed_when_result":true,
   "invocation":{
      "module_args":{
         "_raw_params":"timeout -k 300s 300s /usr/local/bin/kubeadm init --config=/etc/kubernetes/kubeadm-config.yaml --ignore-preflight-errors=all --skip-phases=addon/coredns --upload-certs",
         "_uses_shell":false,
         "argv":null,
         "chdir":null,
         "creates":null,
         "executable":null,
         "removes":null,
         "stdin":null,
         "stdin_add_newline":true,
         "strip_empty_ends":true
      }
   },
   "msg":"non-zero return code",
   "rc":1,
   "start":"2024-03-06 04:53:58.995060",
   "stderr":"W0306 04:53:59.036571   24390 initconfiguration.go:306] error unmarshaling configuration schema.GroupVersionKind{Group:\"kubeadm.k8s.io\", Version:\"v1beta3\", Kind:\"InitConfiguration\"}: json: cannot unmarshal number into Go struct field NodeRegistrationOptions.nodeRegistration.name of type string\njson: cannot unmarshal number into Go struct field NodeRegistrationOptions.nodeRegistration.name of type string\nTo see the stack trace of this error execute with --v=5 or higher",
   "stderr_lines":[
      "W0306 04:53:59.036571   24390 initconfiguration.go:306] error unmarshaling configuration schema.GroupVersionKind{Group:\"kubeadm.k8s.io\", Version:\"v1beta3\", Kind:\"InitConfiguration\"}: json: cannot unmarshal number into Go struct field NodeRegistrationOptions.nodeRegistration.name of type string",
      "json: cannot unmarshal number into Go struct field NodeRegistrationOptions.nodeRegistration.name of type string",
      "To see the stack trace of this error execute with --v=5 or higher"
   ],
   "stdout":"",
   "stdout_lines":[
      
   ]
}

Which issue(s) this PR fixes:

Fixes #10864

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

fix: config hostname as string type in kubeadmConfig rendering

[MrFreezeex]

Thanks :D
/lgtm

[cyclinder]

/lgtm

[ErikJiang]

@mzaian @VannTen @yankay PTAL🙏

[VannTen]

I don't have approval rights you know ^^

[yankay]

Thanks for all @ErikJiang @VannTen
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cyclinder, ErikJiang, MrFreezeex, yankay

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• OWNERS [yankay]

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